UBA2071T/N1,118 NXP Semiconductors, UBA2071T/N1,118 Datasheet - Page 21

• Manufacturer Part Number: UBA2071T/N1,118
• Description: IC DRIVER HALF BRIDGE 24SOIC
• Manufacturer: NXP Semiconductors
• Type: CCFL/EEFL Controllerr

Specifications of UBA2071T/N1,118

• Package / Case: 24-SOIC (0.300", 7.50mm Width)
• Frequency: 38 ~ 42kHz
• Current - Supply: 1.5mA
• Voltage - Supply: 14V
• Operating Temperature: -25°C ~ 100°C
• Driver Type: CCFL Drivers
• Operating Supply Voltage: 14 V
• Maximum Operating Temperature: + 100 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 25 C
• Supply Current: 1.5 mA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 935285139118

NXP Semiconductors
UBA2071_A_1
Product data sheet
8.14.5 Current feedback open or short protection
8.14.6 Overcurrent detection
8.14.7 Arcing detection
times in case overvoltage and overvoltage extra are detected at the same moment (curve
(1)) and if overvoltage, overvoltage extra and hard switching are detected at the same
moment (curve (2)). The first parts of the curves are dashed because an internal filter
makes that VFB needs to be above V
overvoltage extra to react at all.
If a normal overvoltage fault was already present for more than about 840 s before
overvoltage extra detection started or hard switching was already detected for more than
about 55 s before overvoltage extra detection started, then the IC will shut down about
1 s after overvoltage extra is detected.
If the IFB pin is left open or shorted to SGND, the peak of the absolute value of the voltage
at the IFB pin will be below the IFB open/short protection threshold V
fault timer is started.
The IFB open/short protection looks only at the IFB pin voltage if the voltage at the CSWP
pin is equal to the voltage at the CVFB pin. During PWM dimming this is when the lamps
are on and in current regulation or voltage regulation (so not during PWM lamps-off period
and not during the re-ignition frequency sweep).
When the peak of the absolute value of the voltage across the current sense resistor
(connected to the IFB pin) exceeds the OC reference level V
oscillating at f
fault timer is started.
If arcing occurs, for instance due to a bad lamp connection, it causes repetitive short
current spikes that can be seen as voltage spikes at the IFB input. The arcing detection
circuit is directly connected to the IFB pin, so it can only see spikes with a positive polarity.
Usually that will be sufficient. It can detect spikes with amplitude above V
Fig 16. Shutdown time at over voltage extra detection
sw(max)
stop time
, overcurrent is detected. As result PWM dimming is disabled and the
( s)
500
400
300
200
100
Rev. 01 — 23 June 2008
0
0
20
th(ovextra)(VFB)
(2)
(1)
40
Half bridge control IC for CCFL backlighting
UBA2071; UBA2071A
60
VFB above OVE (%)
for at least about 1 s for the
80
014aaa112
th(ocd)(IFB)
100
th(osp)(IFB)
and the IC is
© NXP B.V. 2008. All rights reserved.
th(det)arc(IFB)
and the
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